I know S&W has made J frame snub nosed 9mm revolvers and larger frame competition 9mm revolvers like the 986 and 927, but the model 547 K frame 4” fixed sight revolver was a new one to me.
https://www.gunbroker.com/item/894251209
I see the rationale behind the snubs; decent ballistic performance from the 9mm in a 2” revolver coupled with faster reloads with moon clips... and low recoil-high round count competition guns with the same quick reload capability... but was there much of a call for a 4” 6-shot fixed sight K frame?
Just wondering out loud if anyone has any ideas...
Stay safe.
What Jim Watson said. In the 1970's, European cops began having to shoot people more, and got shot back at more. The Munich Olympics, the Red Brigades in Italy, the Baader Meinhof gang in Germany, Palestinian terrorists, all began making them question whether 32 ACP was still the hot setup it had been back in 1900. By the late 70's they were looking for new artillery. Almost all US cops still carried revolvers then, then so our advice was to get wheelguns in 357 Magnum/38 Special. A lot of the Europeans blanched at that, although Manurhin in France and Astra in Spain began making 357s. Most of the Europeans liked 9mm Parabellum, for commonality with their armies.
So some people had the bright idea to offer them the best of both worlds: revolvers in 9mm. The Smith & Wesson Model 547's and the Ruger 9mm Speed Sixes are both the result of this effort, I think. So was the revolver Astra made for FN as the "Barracuda"; it had interchangeable 357 Magnum and 9mm Parabellum cylinders with a quick release cylinder retainer, for those who wanted
all the choices. (Astra sold it under their own name too, but I can't remember what they called it.)
None of these got much traction. The French and the Spanish got into 357 revolvers to some extent, probably because they had domestic suppliers. The European security forces in general went with 9mm automatic pistols, since they had been using automatics since before World War I and regarded revolvers as quaint antiques. Manufacture of the 547 and the 9mm Ruger revolvers did not last very long.
S&W really put effort into the 547, though. They come up with a trick extractor to allow use of the rimless 9mm round without clips, and it worked very well. It does not look substantial, but IIRC, S&W claimed it would sheer through the rim of a badly stuck brass cartridge case without damaging itself.
Furthermore, they realized that 9mm ammunition is made practically everywhere on earth, and there could be enough difference in dimensions to cause problems, especially since 9mm headspaces on the case mouth and therefore difference in overall length can cause either light strikes or punctured primers. So they came up with a moving section of the standing breech, that would move forward when the trigger was pulled but which would be stopped by the case head and then locked in position until the trigger was released (somehow). This allowed the firing pin to make solid contact without going far enough forward to pierce the primer. I don't know of anything else like it.
All of this sounds like a mechanical nightmare, but it all seems to have worked well, and people who have the guns (like me) like them. I think S&W put extra care into making them probably because they had to. The only negative thing I would say about them is that they are now very heavy for a 9mm Parabellum pistol.
Ruger, on the other hand, just used moon clips for extraction and headspacing and called it a day. I suppose there is a case to be made that the S&W 547 is over-engineered. Certainly it is a bit odd that S&W rejected the use of moon clips as a first principle, despite having
invented them.
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